HDD important issue

With the Western Digital hard drive (not SSD), there is an important issue: using the APM (Advanced Power Management) there are too nomerous spin-down, that can damage the hard drive. To confirm this issue you have to install smartmontools:

# pacman -S smartmontools

And you have to run multiple times this command (once in a minute for like 5 minutes):

# smartctl -a /dev/sda|grep Load_Cycle_Count

If the number under Load_Cycle_Count is increasing in a small amount of time (1 or 2 in a minute) you have this issue.
The problem is easily solvable using laptop-mode-tools. In your /etc/laptop-mode/laptop-mode.conf you have to set:

This disable all power management systems of the hard drive cause a light heat up (maybe). The same behaviour can be obtained running this command:

# hdparm -B 255 /dev/sda

the 255 number is the power-management level, in a range of 1-255 where 1 is maximum powersaving and 255 powersaving disabled. However setting the value to 253 causes a lot of spin-down. Setting the spin-down feature (it parks the heads away from disk) however can save hdd in case of fall.

nVidia ION 2 with Optimus

Optimus doesn't work at all but it is possible to choose which graphical card will be used on next reboot.

You can get 2 'modes' :

By default (if you don't do anything) the machine starts with the Nvidia beeing the only VGA controller visible (so it will use the ION chip).

Using some tools you can start with the Intel and Nvidia VGA controller visible. In this mode the Intel controller is used and it's possible to powerdown the Nvidia part.